Host variables are used to pass information between an
application program and ALLBASE/SQL. They are ordinary
application program variables that happen to be used in
SQL commands.
A host variable name must be preceded by a colon (:) when
used in an SQL command. When used elsewhere in an application
program, no colon should be used.
Host variable names must conform to ALLBASE/SQL's
rules for basic names; however, they are allowed to be up to 30 bytes in
length. In addition, host
variable names must conform to the rules of the language in which the
application program is written.